FIG. 1 is a longitudinal cross-sectional view showing a construction of a SOJ (small outline J-lead) semiconductor package where the external lead has a shape of "J". The conventional semiconductor package includes a semiconductor chip 1 bonded on a paddle 2 by an adhesive 7 and a lead structure having a plurality of internal leads 3 wire-bonded to the semiconductor chip 1 and external leads extending from the internal leads 3. A plurality of metal wires 5 electrically connects the chip 1 and the internal leads 3 of the lead structure, and a molding resin 6 forms the body of the semiconductor package by sealing a predetermined area including the semiconductor chip and the internal leads 3.
When the conventional semiconductor is mounted on the substrate, the occupying area of a package becomes larger due to the external leads protruding from the sides of the semiconductor package body. The occupying area rate becomes higher; the mounting rate is lowered; and an external lead is undesirably curved. Further, since only one chip can be mounted in one package, a multi-chip package is difficult to achieve and a center pad-type semiconductor chip is difficult to package.